n = int(input())
g = [input() for _ in range(n)]
ans = 0
for i in range(n):
    if g[i].count("A") == n - 1 and "B" not in g[i]:
        ans += 1
for j in range(n):
    t = []
    for i in range(n):
        t.append(g[i][j])
    if t.count("A") == n - 1 and "B" not in t:
        ans += 1

t = []
for i in range(n):
    t.append(g[i][i])
if t.count("A") == n - 1 and "B" not in t:
    ans += 1
t = []
for i in range(n):
    t.append(g[i][n - i - 1])
if t.count("A") == n - 1 and "B" not in t:
    ans += 1
print(ans)